In situ characterization methods

In Situ Characterization. As a result of this study, it is clear that Co or other metals may play a dual catal)hic role catalyzing both the growth of nanowires and the production of airborne Si species, such as silane, which acts as a silicon source. An in situ characterization method will eventually be needed. 

Bentrup U. Combining in situ characterization methods in one set-up looking with more eyes into the intricate chemistry of the synthesis and working of heterogeneous catalysts. Chem Soc Rev. 2010 39 4718. 

Interfaces in electrochemical environments can be studied by ex situ and in situ characterization methods. Here, we focus on a few prominent contributions of these methods to the characterization of the electrochemical interface of PtjM bulk alloys and Pd metal overlayers on Au(lll) and Pt(lll). 

Characterization of zeolites is primarily carried out to assess the quality of materials obtained from synthesis and postsynthetic modifications. Secondly, it facilitates the understanding of the relation between physieal and chemical properties of zeolites and their behaviour in certain applications. For this task, especially, in situ characterization methods have beeome increasingly more important, that is, teehniques whieh probe the zeolite under actual process eonditions. 

In situ spectroscopy is the only approach to obtain reliable information on mechanisms and the role of intermediates in chemical reactions as well as on structure-reactivity relationships in catalysis [1-5]. Especially, in heterogeneous catalysis, the application of a variety of in situ methods has gained a lively development during the recent two decades. But also in homogeneous catalysis, as well as in catalytic multiphase systems, in situ characterization methods are increasingly applied. A survey of techniques, which are most commonly applied in gas/soUd and multiphase systems and the method-specific information, is presented in Table 3.1. 

Using a combination of several in situ characterization methods to look at working catalysts, and catalytic reactions, from different perspectives, represents a substantial step toward elucidating the chemistry of catalyst materials and associated reaction mechanisms. 

Novak R, Goers D., Hardwick L., Holzapfel M., ScherfeleW., Ufheil J., Wttrsig A. Advrmced in situ characterization methods applied to carbonaceous materials, J. Power Soirrces 2005, 146, 15-20. 

Bentrup, U. (2010). Combining In Situ Characterization Methods in One Set-Up Looking with More Eyes into the Intricate Chemistry of the Synthesis and Working of Heterogeneous Catalysts, Chem. Soc. Rev., 39, pp. 4718-4730. 

For the in situ characterization of modified electrodes, the method of choice is electrochemical analysis by cyclic voltammetry, ac voltammetry, chronoamperometry or chronocoulometry, or rotating disk voltametry. Cyclic voltammograms are easy to interpret from a qualitative point of view (Fig, 1). The other methods are less direct but they can yield quantitative data more readily. 

As the reader might have noticed, many conclusions in electrocatalysis are based on results obtained with electrochemical techniques. In situ characterization of nanoparticles with imaging and spectroscopic methods, which is performed in a number of laboratories, is invaluable for the understanding of PSEs. Identification of the types of adsorption sites on supported metal nanoparticles, as well as determination of the influence of particle size on the adsorption isotherms for oxygen, hydrogen, and anions, are required for further understanding of the fundamentals of electrocatalysis. 

Similarly, several works can be cited on cationic SIP on flat substrates. Again, the advantage of cationic SIP is that it puts at one s disposal surface-sensitive spectroscopic methods that allow successful in situ characterization of polymer brushes on surfaces ... 

Recent developments in surface-characterization methods have been made possible to a great extent by technological advances in areas such as lasers, ultra-high vacuum, charged-particle optics, and computer science. The surface-analysis techniques are commonly used to probe the interface between two phases after one phase is removed, but there is now a growing demand for additional methods for in situ interface characterization. 

Madhusoodana CD, Das RN, Kameshima Y, Yasumori A, and Okada K. Characterization and adsorption behavior of ZSM-5 zeolite film on cordierite honeycombs prepared by a novel in situ crystallization method. J For Mater 2001 8(4) 265-271. 

It is relatively straightforward to apply the NIR method for in situ characterization work, as was reported in the case of the EFGR tyrosine kinase inhibitor 4-(3-ethynylphenylamino)-6,7-fc/s(2-methoxyethoxy)quina-zolinium methanesulfonate.82 NIR spectroscopy was used to monitor the kinetics of transformation between the polymorphs and solvatomorphs, and... 

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